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arXiv · 2510.25619

Photoelectric detection of single spins in diamond by optically controlled discharge of long-lived trap states

A. C. Ulibarri·D. J. McCloskey·D. Wang·N. Dontschuk·A. M. Martin·A. A. Wood
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Abstract

Electrical detection methods for solid-state spins are attractive for quantum technologies, being readily chip-scalable and not subject to the small photon budgets of single emitters. However, realising electrical spin readout in wide-bandgap materials with similar fidelity and bandwidth to optical approaches remains challenging. Here, we introduce a photoelectrical spin readout scheme that detects spin information stored long-term as trapped electrical charges. Using nitrogen-vacancy (NV) centres in diamond as a model system, spin-dependent photoionisation generates charge carriers that are stored in long-lived trap states at a diamond-metal Schottky junction. On-demand illumination of the junction under electrical bias releases stored charge, yielding a photocurrent transient proportional to the amount of trapped charge and hence spin state. Spin readout after coherent control of single NVs is demonstrated using charge readout in a protocol we call charge-capture detected magnetic resonance (CCDMR), and we use charge-based imaging to identify charge carrier generation and trapping processes. Our results establish CCDMR as a new technique for solid-state spin qubit readout, combining attaractive features of electrical detection with the stability of long-lived charge traps in wide-bandgap materials.

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A. C. Ulibarri, D. J. McCloskey, D. Wang, N. Dontschuk, A. M. Martin, A. A. Wood. 2025-10-29. Photoelectric detection of single spins in diamond by optically controlled discharge of long-lived trap states. https://arxiv.org/abs/2510.25619

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